UpdraftPlus might be a bit more popular than Duplicator Pro. We know about 1 link to it since March 2021 and only 1 link to Duplicator Pro. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
2, The logical way would be to develop the site on a staging/ dev server then move it to their live site when ready. A few things, again, need to be considered, but, for a straightforward swap, you can use a plugin like Duplicator Pro to 'duplicate' your updated version and overwrite the live site when ready. Source: over 2 years ago
First, run a site backup -- both the database and static files on the server (e.g., theme files, image uploads). Ideally you'll also know or figure out how to restore the site with said backup. The plugin UpdraftPlus has a free tier you might start with. I use it on a personal site to run daily backups automatically, and have used it on employer websites in the past. You should be running daily backups if you... Source: 10 months ago
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